1. Field of the Invention
This invention relates generally to surgical clamps and more specifically to clamps which adjustably engage and hold surgical instruments in a generally fixed relationship with a body structure such as a body wall.
2. Discussion of the Prior Art
In the past it has been desirable to hold surgical instruments, such as trocars, in a generally fixed relationship with body structures, such as the abdominal wall. In order to provide for an adjustable relationship between the trocar and the abdominal wall, the clamp has been generally fixed to the abdominal wall but adjustable with respect to the trocar.
The adjustable relationship between the clamp and trocar has been facilitated by a clamp having an elastomeric sleeve sized to receive the trocar in a frictional relationship. A constricting device such as an adjustable collar has been positioned around the sleeve to constrict the sleeve around the trocar. A screw has been provided to tighten the collar and thereby enhance the frictional relationship between the sleeve and trocar. The same screw has been adjustable to relieve the frictional relationship between the sleeve and the trocar thereby permitting the trocar to be maneuvered relative to the body wall.
The prior art also includes adjustable collars which are adjustable in diameter by operation of a circumferential lever between a locked position and a released position. In order to facilitate a generally fixed relationship between the clamp and the abdominal wall, an extension tube has been provided axially of the sleeve and collar. These extension tubes have been formed with helical projections which not only facilitate operative placement of the clamp but also enhance the generally fixed relationship between the clamp and abdominal wall.
In these devices of the prior art, the clamp must be held in one hand in order to operate either the adjustment screw or the lever with the other hand. As a consequence, the simple adjustment of the trocar relative to the body wall has required full attention to operation of the clamp. While other surgical steps and procedures jealously compete for the surgeon's time and attention, the complex structures associated with the clamps of the prior art has demanded that both hands be used in order to adjust the clamp. The structures of the past also involve several parts which must be separately manufactured and assembled to provide the finished clamp. This of course has increased the cost of the product.